Controlled Spatiotemporal Signal Presentation within High-Density Cell Culture Systems for Engineering Complex Tissues

Seminar given by: Eben Alsberg, Ph.D.

Richard and Loan Hill Professor

Dept. of Bioengineering, UIC

Abstract: Tissue engineering holds the promise of producing functional biological replacements to treat lost or damaged tissues. Biomaterials can be designed to partially recapitulate the intricate signals that are implicated in tissue development and healing to regulate cell gene expression and new tissue formation. This talk will introduce high-density cultures of cells that can mimic immature condensates present during many developmental and healing processes. Delivering specific soluble signals exogenously in tissue culture media can regulate cell behavior in these cultures and promote new tissue formation. However, shortcomings of this approach include transport issues, limited spatial control over signal presentation, and required repeated dosing in the media. Incorporating biopolymer microparticles containing bioactive signals within the high-density cell cultures can overcome these challenges and permit localized spatial and temporal control over the presentation of regulatory cues to the cells. I will present our research using this strategy to engineer a variety of tissues, including bone, cartilage and trachea. The capacity to deliver diverse signals, including growth factors and plasmid DNA, for driving new tissue formation will be demonstrated. In addition, the value of this technology for engineering a wide range of tissue shapes, including spheres, sheets, rings and tubes will be examined. Finally, the utility of providing cell-instructive bioactive factors from biomaterials in a controlled manner for the assembly of modular tissue units to engineer complex constructs comprised of multiple tissue types will be explored.